Binding of the PX domain of p47phox to phosphatidylinositol 3,4-bisphosphate and phosphatidic acid is masked by an intramolecular interaction
Open Access
- 1 October 2002
- journal article
- research article
- Published by Springer Nature in The EMBO Journal
- Vol. 21 (19) , 5057-5068
- https://doi.org/10.1093/emboj/cdf519
Abstract
P47 phox is a key cytosolic subunit required for activation of phagocyte NADPH oxidase. The X‐ray structure of the p47 phox PX domain revealed two distinct basic pockets on the membrane‐binding surface, each occupied by a sulfate. These two pockets have different specificities: one preferentially binds phosphatidylinositol 3,4‐bisphosphate [PtdIns(3,4)P2] and is analogous to the phophatidylinositol 3‐phosphate (PtdIns3P)‐binding pocket of p40 phox , while the other binds anionic phospholipids such as phosphatidic acid (PtdOH) or phosphatidylserine. The preference of this second site for PtdOH may be related to previously observed activation of NADPH oxidase by PtdOH. Simultaneous occupancy of the two phospholipid‐binding pockets radically increases membrane affinity. Strikingly, measurements for full‐length p47 phox show that membrane interaction by the PX domain is masked by an intramolecular association with the C‐terminal SH3 domain (C‐SH3). Either a site‐specific mutation in C‐SH3 (W263R) or a mimic of the phosphorylated form of p47 phox [Ser(303, 304, 328, 359, 370)Glu] cause a transition from a closed to an open conformation that binds membranes with a greater affinity than the isolated PX domain.Keywords
This publication has 51 references indexed in Scilit:
- Phosphatidylinositol 3-Phosphate Induces the Membrane Penetration of the FYVE Domains of Vps27p and HrsJournal of Biological Chemistry, 2002
- Chronic granulomatous disease mutations and the PX domainNature Cell Biology, 2002
- Solution Structure of the Vam7p PX Domain,Biochemistry, 2002
- The NADPH Oxidase Components p47phox and p40phox Bind to Moesin through Their PX DomainBiochemical and Biophysical Research Communications, 2001
- The PX Domain as a Novel Phosphoinositide- Binding ModuleBiochemical and Biophysical Research Communications, 2001
- JFC1, a Novel Tandem C2 Domain-containing Protein Associated with the Leukocyte NADPH OxidasePublished by Elsevier ,2001
- Roles of Ionic Residues of the C1 Domain in Protein Kinase C-α Activation and the Origin of Phosphatidylserine SpecificityJournal of Biological Chemistry, 2001
- Activation of the Phagocyte NADPH Oxidase Protein p47Journal of Biological Chemistry, 1999
- Refinement of Macromolecular Structures by the Maximum-Likelihood MethodActa Crystallographica Section D-Biological Crystallography, 1997
- The CCP4 suite: programs for protein crystallographyActa Crystallographica Section D-Biological Crystallography, 1994